这是我得到的：

SELECT DISTINCT Zipcodes.CountyID,us_co_est2005_allData.PopEstimate2005,us_co_est2005_allData.EstimatesBase2000,users_link_territory.userID
FROM
Zipcodes Inner Join Users_link_territory ON zipcodes.CountyID = 
Users_link_territory.CountyID Inner Join
us_co_est2005_alldata ON zipcodes.FIPS = us_co_est2005_alldata.State AND zipcodes.code
= us_co_est2005_alldata.County
WHERE (users_link_territory.userid = 4)

这给了我34行,为每个属于userid4的县提供不同的人口数量,但我如何得到PopEstimate2005和EstimatesBase2000的SUM？

像(但这不是一个合法的查询)：

SELECT DISTINCT Zipcodes.CountyID,SUM(us_co_est2005_allData.PopEstimate2005) AS Population2005,SUM(us_co_est2005_allData.EstimatesBase2000) AS Population2000,users_link_territory.userID
FROM
Zipcodes Inner Join Users_link_territory ON zipcodes.CountyID = 
Users_link_territory.CountyID Inner Join
us_co_est2005_alldata ON zipcodes.FIPS = us_co_est2005_alldata.State AND zipcodes.code
= us_co_est2005_alldata.County
WHERE (users_link_territory.userid = 4)
GROUP BY users_link_territory.userid

当然,只要我将Zipcodes.CountyID添加到GroupBy的末尾,我就会再次回到我的34行.

非常感谢您的帮助.

拉塞尔舒特
.
.
.
.
.

获得以下帮助后 – 特别是Robb的帮助 – 我能够得到我真正想要的东西 – 在一个查询中总共有每个UserID的人口详细信息：

SELECT     SUM(POPESTIMATE2005) AS Expr1,SUM(ESTIMATESBASE2000) AS Expr2,UserID
FROM         (
    SELECT DISTINCT zipcodes.CountyID,us_co_est2005_alldata.POPESTIMATE2005,us_co_est2005_alldata.ESTIMATESBASE2000,users_link_territory.UserID
    FROM          zipcodes INNER JOIN
    users_link_territory ON zipcodes.CountyID = users_link_territory.CountyID INNER JOIN
    us_co_est2005_alldata ON zipcodes.FIPS = us_co_est2005_alldata.STATE AND zipcodes.Code = us_co_est2005_alldata.COUNTY
    ) As FOO
GROUP BY UserID

谢谢大家的贡献！

拉塞尔舒特